C5 X7 'Suspension Fault'.

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RigStodder
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C5 X7 'Suspension Fault'.

Post by RigStodder »

Hi,

I've got a Citroen C5 X7 Tourer from 2009 with 300k km on the clock. It's a great car, but...

Så i've tried to change the two front spheres depressurize and all that jazz, using Lexia. (Later I found that i properly should have used Diagbox; I'm using Diagbox now.)

But I get 'Suspension Fault' when turning on the car and it won't lift it self from the ground. When I check faults with Diagbox, under suspension, I get:
U1117 Supplier Fault Code, Owenership not referenced.
U2005 Triggering (vehicle speed receipt anomaly).

The rear height sensor is at this time frozen with rust, as I can't lift the car from the ground without digging a hole for the jack.

Any ideas ??

Mikael..
RigStodder
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Re: C5 X7 'Suspension Fault'.

Post by RigStodder »

And I've checked all the fuses and replaced the motor for the hydraulic pump, reusing the old motor/hydraulic ecu.
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GiveMeABreak
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Re: C5 X7 'Suspension Fault'.

Post by GiveMeABreak »

U2005 can be ignored - it is simply a symptom of the diagnostic equipment interrogating the suspension ECU when the car is not actually moving.

U1117: Dialogue with the suspension ECU: Absence of communication. So with this fault, it is unlikely you will get any height correction taking place if the suspension ECU is not communicating - as it very likely won't be getting any height information in order to authorise height adjustment.

I would focus on your wiring connections at the connectors of the BHI - check the cleanliness of the pins and sockets and check for loose wiring.
RigStodder
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Re: C5 X7 'Suspension Fault'.

Post by RigStodder »

Okay.
So I've changed the BSI (BSM) unit, on advice from a friend.

Now I'v only got two U1116 and still the U2005.

But still Suspension Fault, when I start the car.
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GiveMeABreak
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Re: C5 X7 'Suspension Fault'.

Post by GiveMeABreak »

Ok, so as I mentioned previously, ignore U2005 for now.

Your U1116 issue is still related to communications issues with the suspension ECU. The fault is similar whether looking at the Suspension ECU, Inflation Detection System, Directional Lights (if these were fitted) etc., all these systems rely on data from the suspension ECU. All these are U1116 faults, depending on the system you are looking at:
  • Absence of body movement sensor information fault information fault
  • Suspension System ECU missing: Absence of communication
  • Suspension ECU data not valid fault: Protocol controller not functional
  • Absence of communication on the CAN with the suspension ECU: Not characterised
  • Suspension systems ECU absent fault
So all these faults say the suspension ECU is not communicating. So I would be focussing on this area and checking to make sure you have power to the connection on the BHI and all the pins are clean, with no contamination or LDS fluid that have possibly got in.
RigStodder
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Re: C5 X7 'Suspension Fault'.

Post by RigStodder »

I have changed the electric motor on the hydralic pump, I bought a complete pump with motor and BHI at that time. I still have the other BHI, can I connect that one, without connection the BHI on top of the pump? In that case I can see if my current BHI is faulty.
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GiveMeABreak
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Re: C5 X7 'Suspension Fault'.

Post by GiveMeABreak »

That's new info you didn't mention before. Be aware that the suspension ECU is on top of the BHI and these have to be correct for the vehicle in question - you can't just swap these between vehicles as they are set up differently depending on engine, model and suspension system (the 4 cylinders use only this suspension ECU, whereas the 6 cylinder engines use both this ECU on the BHI and a separate suspension ECU).

So it may be that either the replacement BHI is incorrect for your car, or faulty itself. So you need like for like if replacing it. If it was just the motor that was faulty originally, then I suggest you try fitting your old suspension ECU back onto the new unit as it will already be coded and set up correctly for your vehicle.
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Re: C5 X7 'Suspension Fault'.

Post by RigStodder »

I know.
I only changed the motor, not the BHI. The setup is from a C5 mk2, so I didn't replace my BHI or the pump.

just a suggestion to swap them around to see if the U1116 disappeared without replacing the BHI on top of the pump.
RigStodder
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Re: C5 X7 'Suspension Fault'.

Post by RigStodder »

I thought the motor was bad as there is an 80A fuse in my car (it should only be 40A maxifuse). Unfortunately, my old motor for the pump looked really nice.
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Re: C5 X7 'Suspension Fault'.

Post by RigStodder »

After that swap everything was ok, but after some aerobic, I got 'Suspension Fault' and the error codes.
MGmike
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Re: C5 X7 'Suspension Fault'.

Post by MGmike »

Have you checked the fuse inside the car? The maxi fuse only drives the motor and there is a second fuse for the BHI electronics, usually in the passenger compartment fuse box (probably a small extra fuse rail above the BSI, at least it is on a C6).

If that's okay you can connect the C5 BHI without attaching to the pump. It obviously won't drive the valve block but the communication error will disappear if your unit is faulty and a different (compatibility) error should be present. I had similar issues with a C6 and eventually fitted a complete spare from another C6. If you do need to change out the BHI (as Marc says above) you will need the exact matching unit from a car with the same type of suspension.
RigStodder
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Re: C5 X7 'Suspension Fault'.

Post by RigStodder »

OK. The error has been found and removed. It was the control for the hydraulic pump that had lost its settings?!? A manual configuration and it raises and lowers again.

HOWEVER, it does not raise / lower the front. I have changed the height sensor on the front.
Anyone there that a photo how the connection rod (from the sensor to the sway bar) should sit (in case I have put mine wrong) or should some sort of calibration be done after sensor change?
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GiveMeABreak
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Re: C5 X7 'Suspension Fault'.

Post by GiveMeABreak »

This is the correct removal / refitting procedure that may help you cross reference.

Fine adjustments are carried out using the standard height checking and measurement procedure - but only fine adjustments.
X7 Front Height Corrector.PNG
Unclip:
  • The connector (at "c")
  • The connector (at "d") (according to equipment)
  • The connector (at "e")
Uncouple the rod (8) from the lever (9).
X7 Front Height Corrector B.PNG
Remove the bolt (10).
Remove the front height sensor (11) through the wheel arch.

Refitting
X7 Front Height Corrector C.PNG
Peg: The height sensor (at "g") using a TORX socket wrench 25.

Refit the front to fight sensor (11) to the support (12).

N.B. : Position the lug "f" on the support (12).

Hold the height sensor (11) in position.
Refit bolt (10). Tighten to 0,4 ± 0,1 daN.m.

Remove the setting rod from the height sensor.

Couple the rod (1) on the lever (2).

Clip:
  • The connector (at "e")
    The connector (at "d") (according to equipment)
    The connector (at "c")

    Connect:
    • The connector (at "b") (according to equipment)
    • The connector (at "a")
    Refit:
    • The yokes (6)
    • The bolts (7) Tighten to 10 ± 1 daN.m
    • The bolts (5) Tighten to 14 ± 1,4 daN.m
    • The clip (4)
    • The nut (3) Tighten to 2,5 ± 0,3 daN.m
    • The (2) bolt Tighten to 6 ± 0,6 daN.m
    Pull the lifting tool from under the front subframe.
    Refit the front wheels.

    Tighten the wheel bolts.
    Return the vehicle to its wheels.
RigStodder
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Re: C5 X7 'Suspension Fault'.

Post by RigStodder »

Thanks Marc. I think that I have to try again. If I remember correct, my bone is conneced so the sensor 'on the top'.
RigStodder
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Re: C5 X7 'Suspension Fault'.

Post by RigStodder »

Refitted the rod and the car raises and lowers again at both ends :-D

Thanks for the help =D>